Road texturing machine

ABSTRACT

A self-propelled and automatically steered machine for selectively imparting longitudinal and transverse grooves or antiskid marks in green concrete.

States Patent 1191 Barton Nov. 27, 1973 [54] ROAD TEXTURING MACHINE 3,605,579 9 1971 Heltzel 94/45 R 2,543,966 3 1951 H ltz 1 94 45 R [751 Inventor! when Bam", Oklahmna 2,601,277 6l952 Greer: 9445 R 2,864,452 12/l958 Guntert 94/46 R 3,377,932 4/1968 Atkinson 94/46 R x [73] Assgnee' 8% Cmmmwn Oklahoma 3,423,859 1/1969 Swisher 37/108 3,529,51s 9/1970 Crone 94/46 R [22] Filed: July 22, 1971 3,516,339 6/1970 Perkins 94/45 R 3,516,340 6 1970 Perkins 94 45 R [21] Appl. No.1 165,214

Related US. Application Data Continuation-impart of Ser. No. 858,070, Sept. 15, l969.

us. 121. 404 93,299/36 1111. 1:1. E016 23/16 1 16111 61 Search 94/46, 45; 299/36 References Cited UNITED STATES PATENTS l 1/1970 Swisher 94/46 R Primary ExaminerNile C. Byers, Jr.

Att0rney-Jerry J. Dunlap, William R. Laney, Robert M. l-lessin, C. Clark Dougherty, Jr., Charles A. Codding and John M, Fish, Jr.

[5 7] ABSTRACT A self-propelled and automatically steered machine for selectively imparting longitudinal and transverse grooves or antiskid marks in green concrete.

17 Claims, 25 Drawing Figures PATENTED NOV 2 7 I973 SHEET 2 BF 9 SHIT 3 OF 9 PATENTEU NOV 2 7 I975 PATENTEDHBV 27 [m SHIFT 5 Ci ROAD TEXTURING MACHINE This application is a continuation-in-part of my copending application, Ser. No. 858,070, filed Sept. 15, 1969, now abandoned.

The present invention is directed to new and useful improvements in methods and apparatus for imparting antiskid textures to roads while the roads are in a relatively soft, uncured condition.

For years, the road building art has considered various ways and means for imparting selected textures to the surface of road of both asphalt and concrete for the purpose of increasing wear qualities and also for the purpose of increasing frictional engagement between the road and the vehicle wheels which traverse the road. It has been more or less customary in the concrete road building art to use a burlap drag after concrete has been laid in the road bed and while the concrete is still green or in an uncured state. Usually the burlap is passed longitudinally over the road surface to impart light longitudinally extending score marks in the surface of the concrete. In some cases, road building contracts have required brooming of the green concrete surface to impart score marks which are more definitely defined in the surface of the road. Brooming machines have been used which pass longitudinally of the road bed while a broom carried by the machine is driven transversely of the road bed. Machines of this type impart more or less diagonal score lines in the concrete due to the combined longitudinal and transverse movement. While scoring through the use of burlap and brooming tends to improve the antiskid character of roads, attention has been given recently to the use of more pronounced score lines in concrete and asphalt for the purpose of both promoting drainage and for increasing the frictional qualities of the road surface. Some thought and practice has been directed to the use of saws which create score lines in concrete or asphalt with the score lines being approximately l/8 to H4 inch wide and in depth and at intervals of approximately 3/4 inch and sometimes more. Such cuts have been made transversely of the road and in some cases longitudinal cuts have been proposed. The use of saws or other implements to form grooves or decided score lines in concrete or asphalt after the concrete or asphalt has cured is expensive.

With the foregoing in mind, the major purpose of the present invention is to create a machine which may be used with concrete before the concrete is in its finally hardened state and which allows the user of the machine to quickly and easily impart either longitudinal and/or transverse score lines in the road surface for improving the antiskid character of the road while at the same time promoting drainage from the road surface. In a preferred style of operation of the machine, the operator may cause the machine to be driven in straddling relation to freshly laid concrete and impart continuous longitudinal scoring to all portions of the road surface during movement of the machine while stopping the machine at spaced, selected intervals to impart transverse scoring of the road surface. Transverse scoring may be performed at so-called critical road areas such as curves, entrance and exit ramps and other areas where high antiskid qualities are desired and where good drainage is required.

Related purposes of the invention are to create an apparatus that is easily used with pavement formed by slip form pavers in which no guide rollers are used for the pavement forming machine, to create a scoring machine which automatically follows the shape of a road being treated by the machine, and to so form scoring facilities on a machine that scoring elements are easily adapted to both the transverse and longitudinal slope of a road surface so as to impart a substantially uniform scoring of the road surface.

A still further related purpose of the apparatus of the present invention is to create new and improved scoring elements which are especially useful in impressing scoring grooves at spaced intervals in green concrete without materially gouging or otherwise undesirably displacing the concrete in the road surface.

Other purposes will become more apparent in the course of the ensuing specification and claims when taken with the accompanying drawings, in which:

FIG. 1 is a side view of a typical machine embodying the principles of the present invention;

FIG. 2 is a front view of the machine of FIG. 1;

FIG. 3 is a plan view of a part of the machine illustrated in FIG. 1;

FIG. 4 is a detail view illustrating the connections between a supporting wheel frame and a transverse frame utilized in the invention;

FIG. 5 is a front view of a scoring element carriage used in the invention;

FIG. 6 is an enlarged'side view illustrating a wheel driving mechanism used in the invention;

FIG. 7 is an end view illustrating that portion of the machine steering control which senses and controls the steering for the machine of FIGS. l-S;

FIG. 8 is a perspective view of a wheel position sensing element shown in FIG. 6;

FIG. 9 is a plan view of a scoring element supporting frame and carriage shown in FIG. 5;

FIG. 10 is a side view of the scoring element supporting frame and carriage illustrated in FIG. 9; FIG. 11 is a side view of a scoring element assembly which may be used in the invention, while particularly illustrating an arrangement of elongated resilient plastic strips or equivalent plastic wires that may be used with the invention;

FIG. 12 is a transverse sectional view of a modified subframe for supporting a carriage;

FIG. 13 is a plan view of a portion of the elements illustrated in FIG. 12;

FIG. 14 is a side view of a transverse beam utilized in the subframe of FIGS. 12 and 13;

FIG. 15 is a plan view of a scoring machine similar to that illustrated in FIGS. 1l1 while utilizing modified wheel assemblies and sensing assemblies;

FIG. 16 is a side view of the modified machine illustrated in FIG. 15;

FIG. 17 is a front view of the modified wheel assembly illustrated in FIGS. 15 and 16;

FIG. 18 is an end view of a modified form of scoring element;

FIG. 19 is a side view of the scoring element illustrated in FIG. 18;

FIG. 20 is a plan view of the machine utilized with a tube finisher;

FIG. 21 is a side view of the tube element illustrated in FIG. 20;

FIG. 22 is a perspective view of a modified form of scoring assembly attachable to the movable carriage of the machine illustrated in FIGS. 1, 5, 9, 10 and 16;

FIG. 23 is an enlarged perspective view of a portion of the scoring assembly illustrated in FIG. 22;

FIG. 24 is a side view of the scoring assembly illustrated in FIG. 22; and

FIG. 25 is a front view of a portion of the assembly illustrated in FIG. 22.

With specific reference now to the drawings wherein like elements are designated by like characters throughout, and in the first instance to FIGS. 1, 2, 3 and 4, the numeral generally designates the frame of the machine. The frame is composed of a central frame portion 21 and spaced front and rear portions generally designated 22 and 23. The front and rear portions 22 and 23 are generally each defined by a pair of arms. For example, spaced arms 24 extend forwardly from the central portion while spaced arms 25 extend rearwardly from the central frame portion. Central beam 26 is adapted to be clamped to beams 21a and 21b of the central frame portions. It should be understood that the central frame portion 21 serves as a support for an operator control stand 29, internal combustion engine 30 and hydraulic pumping unit and control assembly 31. The forwardly extending arm 24 and rearwardly extending arm on one side of the frame are fixed to a longitudinally extending beam 26 while the arms 24 and 25 on the other side of the frame are fixed to a longitudinally extending beam 27 (FIG. 3). Beams 26 and 27 are clamped to the central frame structure. Selective lateral spacing of the front arms 24 relative to one another and selective lateral spacing of the rear arms 25 relative to one another may be achieved by loosening clamps diagrammatically shown at 32 which fix the central frame to the beams 26 and 27. By adjusting the position of one or both of the beams 26 and 27 with their associated arms 24 and 25 toward or away from one another a selected lateral spacing is achieved whereupon the clamps 32 are again tightenend to fix the arms and central frame portion together.

The arms 24 and 25 are each pivotally connected to their associated longitudinally extending beam member 26 or 27 as by means of the pivot pins 33 so that the arms 24 and 25 may be pivoted or folded to and from a position generally alongside the central portion of the frame to positions extending outwardly therefrom or generally longitudinally of the machine as illustrated in FIG. 3. The pivot 33 connects a plate 33a carried by the arm 24 to a plate 33b carried by the beams 26. In the outwardly extended and operating position illustrated in FIGS. 1-3, suitable bolts or the like 34 connect the plates in abutting relation and are used to hold the arms in position and prevent pivotal or folding movement. Other means (not shown) may be used to hold the arms 24 and 25 in a folded position alongside the central portion 21 of the frame. The longitudinally extended position is the operating position of the frame arms whereas the position alongside the central portion 21 is the transport position of the arms.

As is seen best in FIGS. 1, 2 and 3, the wheel arm supporting beams 26 and 27 define laterally adjustable subframes between the main frame at each side of the main frame.

FIGS. 15 and 16 illustrate a modified wheel arm support. In these figures the wheel supporting arms 24 and 25 are pivoted to the subframes 26 and 27 at inwardly spaced locations with respect to the frame members 21a and 21b. This allows the wheel supporting arms to be folded underneath the central frame for transport.

It should be understood that, as formed, the machine may be driven in either direction.

As is seen best in FIG. 6, each of the arms 24 and 25 carries an upstanding cylinder 35 at the outer end portion thereof. The cylinders 35 receive wheel posts 36. Suitable bearings 37 are interposed between the cylinder 35 and its associated wheel post 36 so as to allow turning movement of the wheel post 36 within its associated cylinder. Selected adjustment of the upstanding wheel post 36 within the cylinder 35 may be accomplished through use of selective positioning of a holding pin or pins 38 which are passed through a plurality of vertically spaced apertures in the cylinder and wheel post.

The forward wheel posts 36 carry front wheels 39 and 40 while the rearward wheel posts 36 carry rear wheels 41 and 42. Each of the supporting wheels 39, 40, 41 and 42 are journaled for rotation on axles 43 carried by yokes 43a on the lower end of their associated wheel posts 36.

Each wheel post carries a supporting platform 44 at a level above the wheels and beneath the cylinders 35. Platform 44 serves to support a rotary hydraulic motor 45 which is supplied with hydraulic fluid under pressure from the hydraulic control and power unit generally designated at 31 in FIG. 2. The output shaft of each hydraulic motor 45 carries a drive sprocket 46 which drives a chain 47 which extends between the sprocket 46 and a sprocket 48 which is fixed to each wheel for rotation with each wheel. The hydraulic power unit is coupled to each of the rotary hydraulic power motors 45 for each of the wheels in order to supply power to each of the motors 45 simultaneously for rotation of the wheels in the same direction. In this regard, the valve connections in the hydraulic power unit are reversible in a manner known to the hydraulic art in order to drive the wheels in either direction and thus propel the machine in either direction.

The front wheels 39 and 40 are coupled together for simultaneous turning movement through a linkage generally designated at 50 (FIG. 4). The rear wheels 41 and 42 are similarly coupled for simultaneous turning movement together through use of a linkage generally designated at 51. Each of the linkages 50 and 51 are identically formed and hence only the linkage 50 for the front wheels 39 and 40 will be described. Each linkage, for example, includes a slide bar 52 which is mounted for sliding movement in guides 53 on the central portion of the frame and in a direction generally transversely of the longitudinal axis of the machine. The slide bar 52 is pivotally connected, as at 524 and 52b, to connecting links 54 and 55 for the front wheels 39 and 40, respectively. The connecting links 54 and 55 are pivotally connected to crank arms 56 and 57 which in turn are fixed to the wheel posts 36 of the wheels 39 and 40, respectively. Thus, turning movement of one wheel, as for example wheel 39, produces a corresponding turning movement of wheel 40 in the same direction. counterclockwise movement of crank 56 as viewed in FIG. 4 produces movement of link 54 laterally toward the opposite side of the machine and link 54 transmits motion through the sliding action of slide bar 52 to link 55, also thereby causing link 55 to move to the right as viewed in FIG. 3 and this in turn produces counterclockwise motion of crank 57 for wheel 40 to the same extent as the motion produced in wheel 39.

It should be noted that each of the links 54 and 55 is formed from telescoping sections so that its effective length can be varied. They are held at a selected length by pin and aperture connections 58. Thus, when the wheels 39 and 40 are positioned at various spacings from one another, the links 54 and 55 may accommodate this spacing through selective use of the apertures 58.

Turning movement of the front wheels 39 and 40 is produced by an extensible element in the form of a hydraulic cylinder 59 which has the cylinder thereof pivotally mounted on a portion of the arm and the piston rod thereof pivotally connected to a crank 60 which is fixed to and extends from the supporting post 36 of one wheel, as for example wheel 39. Upon extension of the ram in cylinder 59, counterclockwise movement of the wheel 39 as viewed in FIG. 3 is produced. Conversely, retraction of the ram within cylinder 59 produces clockwise rotation of wheel 39 as viewed in FIG. 3. The same rotational movement is produced in the other front wheel 40 by transmission of the forces through linkage 50.

The rear wheels 41 and 42 are turned in unison through use of an hydraulic ram 59a which is connected in the same manner as that described with respect to cylinder 59 for the front wheels 39 and 40.

In accordance with the invention, each of the power cylinders 59 and 59a for the front and rear wheels are operated independently of one another through use of separate hydraulic power systems, all under control of 7 suitable switches and actuating valves in a manner known to the hydraulic art. The front wheels may thus be turned in one direction while the rear wheels may be turned independently in the opposite direction. This independent control of the front and rear wheels is an aid in maneuvering the machine and is also important in terms of holding the machine in a proper position for a scoring operation which will be described later.

FIGS. 15, 16 and 17 illustrate a modified wheel assembly which may be utilized in place of the assembly illustrated in FIGS. 1, 2, 4 a'nd 6-8 In FIG. 17, for example, the wheel supporting arms 24 or 25 are fixed to upstanding tubular posts 120 and a wheel supporting post 121 is journalled for rotation about generally vertical axes in these posts 120. The posts 121 have depending yoke structures 122 which carry the axles of the wheels. The yoke structures are sectionally formed with an inner yoke section 122a within an outer section 122b. The inner section carries the, wheel 41. Height adjustment is accomplished through selective positioning of bolts l22c in spaced apertures 122d in the arms of the two yoke sections.

One end of the frame, as for example what is herein designated as the rear end, may carry suitablepiping facilities generally designated at 63 for supplying water or a cement curing fluid to pavement being processed by the machine of the present invention.

As is seen in FIGS. 1, 2 and 3, the front end of the machine carries a boom 64 which is supported on the arms 24 and 25 through use of pivotal arms 65 which are spaced along and rotatably mounted upon a transverse bar 65a which spans the arms 24 and is connected to the cylinders 35. An hydraulic cylinder 66 is pivotally connected to a frame member 67 extending between bar 65a and the central frame portion, and to one of the arms 65 so as to rotate the laterally spaced arms 65 about the axis of bar 65a and selectively vertically position boom 64 with respect to the surface of the pavement being treated. Boom 64 is adapted to carry scoring elements along the length thereof. The scoring elements may take the form of burlap cloth 64a as has been utilized heretofore in the texturing of concrete surfaces, in which case the cloth is simply clamped or otherwise suitably fixed to the boom 64. On the other hand, boom 64 may be utilized to support other scoring elements as herein disclosed in the form of a brush or broom or in the form of special spaced wire-like looped elements as hereinafter described. In each case, the scoring elements extend transversely of the machine and are positioned along boom 64. Thus, when the machine is driven in the forward direction as herein referred to, the transversely positioned scoring elements may impress score lines extending generally longitudinally of the pavement traversed by the machine.

The central portion of the frame of the machine serves as a support for a subframe 68 which extends transversely of the machine. Subframe 68 is supported from the central portion of the frame through use of cylinder and piston assemblies 69 which are pivotally connected to the central portion of the frame as at 680 and to the subframe as is illustrated at 70 in FIGS. 1 and 10. Thus the subframe 68 may rock about the transverse axis of the pivot connections 70 between the subframe 68 and the piston rod 71 of each of the cylinder assemblies 69. The subframe 68 includes spaced tracks 72 and 73 depending therefrom and the tracks 72 and 73 serve as a guiding support for roller assemblies 74 which are fixed to a supporting carriage 75 in an upstanding relation thereto. Carriage 75 extends generally longitudinally of the machine and includes depending connecting brackets 76. A scoring subassembly, which in FIG. 10 is shown in the form of a broom, includes an elongated backbone 78 with depending filaments 78a. The backbone or support 78 has upstanding spaced support arms 79 fixed thereto and the support arms 79 are adapted to be pivotally mounted on the lower ends of the brackets 76 through use of the pivot pins 80. Springs 79a extend from opposite sides of the carriage to the arms 79 and bias the broom toward the position illustrated in FIG. 5.

Carriage 75 is adapted to be reciprocated transversely of the machine through use of a cable 81 as shown in FIG. 5. Cable 81 is passed around pulleys 82 and 83 at the opposite ends of the subframe 68. Cable 81 is fixed to the carriages as by the connection 84 (FIG. 10). One of the sprockets 83 is adapted to be driven through use of a driven sprocket 86 which is fixed to the shaft of pulley 83 for rotation therewith. A chain 87 drives sprocket 86 from a sprocket 88 of a rotary hydraulic motor 89 which is carried on the subframe 68. Rotation of the pulley 83 in either direction as induced by the motor 89 produces corresponding movement of cable 81 and movement of the carriage and scoring element subassembly of the carriage. Limit switches 90 and 91 are positioned on the subframe at opposite ends thereof with actuating elements 92 adapted to be contacted by the carriage at opposite extremes of movement. When the switch arms 92 are contacted by the carriage, this stops the rotation of fluid motor 89 through suitable electrical connections in a manner known to the hydraulic art, to thus stop the position of the carriage at either extreme of movement. Suitable electrical circuits are provided to enable the operator to then complete circuits to cause energization of motor 89 in the opposite direction.

The subframe 68 includes an upstanding rod 94 which is pivotally connected to one side of the main frame with respect to the pivot axis 70. Rod 94 extends upwardly through the central portion of the frame and is received in a guide tube 95 at a position alongside the operator control stand. The upper end of rod 94 may include a suitable handle or the like 96. The position of rod 94 within the tube 95 may be fixed through use of a suitable set screw 97.

It should be noted that by reason of the pivotal connection between the piston rod 71 and the subframe 68a, tilted disposition of the subframe 68 may be obtained in a desired degree through movement of control rod 94 and thereafter fixing it in a selected position. This allows the operator to fix the position of the scoring element with respect to the general plane of the pavement being treated. This is of importance particularly on inclined pavement sections. Also, it enables the operator to set either the forward or rear end of the scoring elements for a more deep or a more shallow penetrating action as may be desired in certain circumstances.

A modified track and carriage assembly is shown in FIGS. 12-16. As in FIGS. 1 and 2, the hydraulic cylin ders 69 are carried by the wheel subframes and pivotally mounted thereon as indicated at 68a. In these figures, the lower ends of the piston rods 71 are each pivotally connected to beams 71b of the subframe 68 as at 71a so that the subframe may rock about the axis of this pivotal connection which extends transversely of the machine and road bed. The beams 71b are spaced transversely of the machine and are removably clamped to spaced transversely extending outer beams 71c of the subframe 68 as by means of clamping elements 68b(FIG. 12), which overlie these beams, and bolts 680 which are passed through these clamping elements and through the beam 71b. A pair of springs 71d and He may extend between upstanding members 71f on the subframe on opposite sides of the pivots 71a and the piston rods so as to bias the subframe toward a neutral, generally horizontal position. This clamping arrangement allows use of the same basic suspension structure defined by the beams 71b and piston and cylinders with different lengths of beams 71c.

The beams 71c carry the tracks 72 and 73 for the roller assemblies 74 for the carriage as in FIGS, 1, 5 and 10. The carriage 75 is supported from the rollers 74 and reciprocable laterally as in FIGS. 1, 5 and 10, although in FIG. 16 an improved scoring element described hereinafter is shown pivotally connected as at 80 to the support arms 76.

In some cases it may be desirable to control a set angular position of the subframe, in which case an hydraulic cylinder 71g is pivotally connected between the pivot 71h and one member 71f of the subframe so as to enable adjustment of the subframe about the axis of the pivot 71a. When the cylinder 71g is used, the springs 71d and 7le may be omitted. In order to limit the descent of the subframe 68 and carriage to a preselected position to the road, limit cables 75a may be affixed to the beams 71b (FIG. and passed around a sheave 75b carried by the wheel frame beams connected to an extensible actuating screw 750. By turning the handle of the screw, the cable 75a is fed in or out to a selected length. By setting the cable to an appropriate length the descent of the subframe may be limited to a selected height above the road.

As will be seen best in FIG. 14, the beams 71c of the subframe 68 are preferably sectionally formed from a plurality of sections. Separate sections S and S may be pivotally connected together as indicated at P and turn buckles T positioned on adjacent sections to allow relative folding movement of the sections about the pivots. The axes of the pivots are disposed longitudinally of the machine. This allows adjustment of the sections to accommodate varying crowns or relative transverse inclinations of portions of the road.

By forming the wheel subframes as described and with the suspending cylinders for the scoring element subframe and carriage 68 suspended from these subframes while the connecting beams between the cylinder and the subframe are removably positioned along the length of the subframe, the wheel assemblies and central frame are readily adaptable to selected lateral spacings and with various lengths of subframes.

Since the machine of the present invention is specifically intended for use in slip form paving operations or in other operations not having guide rails for the machines to travel on, sensing elements are associated with each of the wheels 39, 40, 41 and 42, as shown in FIGS. 7 and 8, for insuring that the wheels do not contactand thus destroy the fresh pavement. Each sensing assembly for each wheel is identical and hence only a single assembly will be described. Each assembly, for example, includes a support arm 101 fixed to one leg of the wheel yoke 43a. Each arm 101 is adapted to extend generally parallel to the longitudinal axis of the machine when its associated wheel is aligned parallel to the longitudinal axis. Each arm 101 is positioned inwardly of its associated wheel. Arm 101 has a pair of supports 103 and 104 at each end thereof. The supports 103 and 104 are disposed so that an angle of approximately 120 is included between them. One support, for example the support 103, carries a light projecting element 105 whereas the other support of the pair carries a light sensitive element 106.

The supports 103 and 104 as well as the arm 101 are hollow so that suitable electrical wires may lead through these supports and arm from the light projecting element 105 and light sensitive element 106 to the control unit of the machine. Light sensing element 106, when receiving the light beam emanating from the light projecting element 105 is adapted to maintain a circuit energized, whereas when the light beam is broken as by some object extending across the axis of the beam, a switch is closed to thereby actuate the hydraulic power system with the wheel associated with the post 36 carrying the particular light sensing elements.

A separate hydraulic control switch is provided for the front set of elements 105 and 106 and a separate hydraulic control switch is provided for the rear set of elements 105 and 106. Only the forward pair of elements 105 and 106 (with respect to the direction of movement of the machine) are used at one time. When a wheel, as for example wheel 39, is at the correct spatial distance from the edge of the concrete slab being traversed by the machine, the light beams between the element 105 and the element 106 is uninterrupted and the circuit from the light sensing element to the valve which controls the action of the steering motor 59 remains closed, thus holding the hydraulic motor 59 and wheel 39 in a set position. However, when wheel 39 moves more closely to the edge of the slab and is close enough to cause interruption of the beam between one pair of elements 105 and 106, the beam is interrupted which in turn closes a switch in amanner known to the electrical arts and this switch in turn actuates the valve of the hydraulic power unit for motor 59 to cause turning movement of wheel 39 and corresponding counterclockwise movement of wheel 40 so that wheel 39 moves away from the edge of the pavement while wheel 40 moves more nearly to the edge. Hydraulic fluid under control of the valve is supplied to the cylinder 59 until wheel 39 is moved sufficiently far away from the edge of the concrete that the light sensing element 106 again receives an unobstructed beam of light. This in turn closes the valve to the supply of hydraulic fluid and turning movement of wheel 39 is stopped. Turning movement of the wheels 39 and 40 of the front wheels in the opposite direction-is under control of the elements 105 and 106 of other wheel 40. Inthis regard, if the turning movement is such that wheel 39 moves sufficiently far away from its adjacent edge of the slab that wheel 40 moves so close to the edge of the slab that the light beam of its sensing assembly is broken, the valve of the hydraulic unit is reversed to cause retraction of the hydraulic cylinder 59 and a corresponding clockwise movement of the wheels 39 and 40 as viewed in FIG. 3.

The operation of the sensing elements for the rear wheels 41 and 42 is identical to that described for the wheels 39 and 40, although turning movement of the wheels 41 and 42 is independent of any turning movement of the wheels 39 and 40.

It should be noted that by using sensing elements positioned forwardly of each associated wheel with respect to the direction of the movement of the wheel, turning movement of the wheel in turn produces movement of the light beam away from the edge of the pavement. This is advantageous in that it tends to shorten up the amount of turning movement of the wheel. If the turning movement of the wheel has not been sufficient, the light beam will again be broken to produce a furtherincrement of turning movement. In other words, turning movement of the wheel under control of the sensing elements maynot be initially sufficient to bring the wheel into a proper spaced position with respect to the slab because of the movement of the light beam axis away from the slab during turning movement of the wheel. However, if the actual degree of turning movement is not sufficient, the light beam will again be broken to produce the further turning movement.

FIGS. 15, 16 and 17 illustrate modified sensing elements for controlling the steering. In these figures the sensing elements 123 and 124 are carried by an arm 125 which is pivoted on a support arm 126 as at 125a which is in turn fixed to the post 121. A link 127 is pivoted to arm 125 and to the wheel links 56 and 57 so that the arm 125 turns with turning movement of the wheel. Arm 125 has sensing switch structures 128 carried at the opposite ends thereof at positions forwardly and rearwardly of each wheel. These sensing structures 128 include a depending actuating finger" or arm 1284 which is adapted to ride against a grade wire or string. The switch structures are of a type wherein the actuating arms 128 are biased outwardly against the grade line, and when the machine is properly positioned with respect to the grade line, the grade line forces the arm 128a to a neutral position. If the machine moves too close to the grade line, the grade line forces arm 128 about its pivot to a small extent necessary to actuate a microswitch which in turn energizes the control circuit to cause turning movement of the wheel associated with the sensing element in a direction away from the grade line. When the wheel associated with the sensing element is positioned too far away from the grade line, the spring biases the arm 128 toward the grade line to a maximum position where a second switch is closed to energize an appropriate cir cuit to cause turning movement of the wheel in the opposite direction. When the machine is properly positioned with reference to the grade line, the arm is at a neutral position between the two switch contact positions, and the wheel then maintains its particular directional position. Only one sensing structure for each wheel is used at any time. The one used is the one forward of the wheel with respect to the direction of travel.

FIG. 11 illustrates an improved scoring element assembly which may be utilized either with the boom 64 or with the carriage 75. In FIG. 11, scoring elements are defined by relatively flexible wire-like loops 111. These loops 111 are equally spaced along the axis of a support bar 112. Each of the loops l1 1 is identical and may be formed from a plastic or similar material. The loops are held in spaced relation slong the axis of bar 112 through use of a supporting strap 113 which is fixed to the lower surface of the bar 112 and by a tube 114 positioned above each strap. The wire-like loops 111 are passed through apertures as at 115 at the opposite ends of the strap 113 and the ends of the wire-like elements are held within the tube 114 as by means of a set screw 116. The loops are disposed in a generally elliptical form under constraint of the tube 114 and strap 113. The support arm includes supporting hangers 117 which are spaced so as to be coupled to the supporting hangers 76 in FIG. 10 or coupled to similar supporting hangers on boom 64 in FIG. 2.

These wire-like elements have sufficient resilience and flexibility so that when the assembly of elements rests by gravity on green jconcrete, the loops flatten out a bit at their lower portions. These loops are advantageous in that when mounted for movement across the surface of green concrete, the leading portions of the loops gradually depress the concrete whereas the trailing portions of the loops follow in the grooves thus created to provide a generally neat and smooth groove. These elements may be formed of wire-like material approximately l/8 of an inch in diameter so as to produce either transverse or longitudinal grooves of generally matching dimensions. The use of the wire-like elements prevents any substantial distortion or gouging of the concrete surface except for the impressing or scoring action.

FIGS. 18 and 19 disclose another form of scoring element. In this vfigure the scoring element consists of a plurality of straight ribs 131 which are spaced equally along the length of a support bar 132. The ribs and bar may be cast unitarily. The ribs 131 and bar 132 are curved upwardly at at least one side thereof as designated at 131a with a generally straight central portion l31b extending from the upturned side portion to the other side portion. The scoring elements defined by the ribs may be positioned on 2-inch centers along the length of the supporting bar. In use, they are dragged across the surface of the fresh concrete and impress small grooves therein. The rib diameter may be such as to impress grooves approximately 1/8 to 1/4 inch in width in the fresh concrete. The ends of the support bar are carried by the arms 76 of the carriage.

While the machine is illustrated and disclosed for use with scoring elements in the form of brooms, wire-like or ribbed scoring elements, it should be understood that the basic frame organization may be used with other road working tools. For example, the subframe 68 and associated scoring elements may be disconnected from the remainder of the machine and the machine is then utilized to drag other road finishing elements such as an aluminum finishing tube 134 (FIGS. and 21), the use of which is known to the art. For example, the depending piston rods 71 may be connected to supports for such elements.

FIGS. 22-25 illustrate a modified form of scoring assembly. In these figures, a pan 150 made of flat steel plate has a series of equally spaced and generally parallel ribs 151 projecting from the undersurface thereof. Pan 150 has a rectangular outline and is to be moved in the direction of its width. These lineally extending ribs extend from one side of the plate to the other and are adapted to impress grooves in the concrete parallel to the direction of movement of the pan. The ribs 151 may be formed somewhat rounded and dimensioned so as to impress grooves G (FIG. 23) approximately l/4 inch deep and approximately l/4 inch in width in the concrete. These ribs are equally spaced along the length of the pan every 1 1 inches. In a typical example, pan 150 may have a length of about 6 feet and a width of about 2 to 3 feet.

Pan 150 is adapted to be supported from carriage 75 as shown in the preceding figures by means of clamping brackets 152 which are carried above the pan 150 by supporting links 153 and 154. The links 153 and 154 are secured to the pan by means of bolts 155 and are secured to the brackets 152 through bolts 156. These connecting bolts are preferably formed so that they may be locked with the links 153 and 154 in a selected angular upward and forward inclination with respect to the direction of pan movement. The forward edge of pan 150 (with respect to the direction of movement) is curved upwardly slightly as at 150a to avoid digging into the concrete. The downward forces exerted by the pan on the concrete is that due solely to the weight of the pan and elements carried thereby.

Pan 150 carries a vibrating unit on its upper surface. The vibrating unit may take the form of a high speed hydraulic motor 157, the shaft of which is coupled to an eccentric weight assembly 158. The weight rotates about the axis of the motor shaft. The frequency and amplitude of the vibratory forces may vary somewhat but it is generally preferred to have a relatively high frequency and low amplitude of vibration. The undersurface of the pan may thus serve to smooth the surface of the concrete somewhat in a fashion of a vibratory finishing sceed. At the same time the vibration is advantageous in terms of allowing the ribs 151 to impress neat appearing grooves in the concrete.

The trailing edge of the pan 150 carries additional scoring elements in the form of wires 159 which are fixed to the pan by means of a support rod 160 which is positioned above the pan at the trailing edge of the pan by support brackets 161. Wires 159 have a curvilinear form with their upper ends held within the support bar 160. Each of the wires 159 is curved so as to pass through support grooves 162 in the trailing edge of the pan and then extend rearwardly for contact with the concrete a short distance behind the pan, as indicated in FIG. 23. For example, the outermost ends of the wires 159 may be approximately 3 inches from the trailing edge of the pan, while the contact area from the outermost ends of the wires inwardly towards the pan, as indicated by the distance X in FIG. 23, may be approximately 1 .6 inches. The wires 159 have a generally rectangular cross-section with a width of approximately 1/16 inch and a height of on the order of 0.028 inch. The wires 159 are spaced lengthwise of the pan so that they impress relatively light grooves between the grooves G formed by the ribs 151. The wires are equidistantly spaced from one another and positioned to impress equidistantly spaced, parallel, grooves between the grooves G.

The scoring assembly illustrated in FIGS. 22, 23 and 24 may be used to impress grooves extending either lengthwise or transversely of a road surface. Preferably it is used to impress grooves transversely of the length of the road surface. The grooves formed by the ribs 151 are advantageous in terms of providing water runoff troughs from a highway and are also advantageous from the standpoint of providing antiskidding characteristics for a pavement. The relatively light grooves formed by the wires 159 provide a good antiskid surface between the larger grooves G. The scoring assembly illustrated in FIGS. 22-24 may be used just after the final finishing operation on concrete. It should be used while the concrete is still in a somewhat plastic condition.

I CLAIM:

1. A scoring element assembly foruse in forming grooves of small width and relatively shallow depth in green concrete including an elongated supporting frame and resilient, looped wire-like elements carried at generally equally spaced intervals along said frame, said elements being sufficiently resilient and having a shape such that when said frame and loops have their weight essentially supported by a bed of green concrete or the equivalent and are moved transversely to the length of said frame along said concrete, said loops will impress grooves generally parallel to the direction of movement without substantial displacement of said concrete other than in directions generally downward from the general plane of the surface of the concrete.

2. The structure of claim 1 wherein said loops are generally elliptical in form with the major axis thereof generally parallel to the direction of movement.

3. The structure of claim 1 wherein said frame has a supporting strap carried thereby and extending generally parallel to said direction of movement, said strap having forward and rear portions with guiding apertures with said elements extended therethrough.

4. The structure of claim 1 wherein said frame includes support tube associated with each element and with opposite ends of each element secured within said tube.

5. A machine for selectively impressing longitudinal and transverse grooves in the exposed surface of green concrete which ultimately defines a roadway including a supporting frame having spaced supporting wheels formed and adapted to straddle a road defining slab of green concrete, said frame including a first scoring element support extending transversely of the longitudinal axis of the frame, a plurality of scoring elements carried by said support and formed and adapted to impress grooves extending generally longitudinally of said frame and slab when said frame is moved longitudinally of said slab, a second scoring element support extending generally parallel to the longitudinal axis of said frame, said second support including a plurality of scoring elements defined by a plurality of spaced wire-like loops, means for moving said second support generally transversely of the longitudinal axis of said slab to impress transverse grooves in said slab, means for moving said frame in said longitudinal direction, and means for intermittently moving said second support transversely of said longitudinal axis.

6. A machine for selectively impressing longitudinal and transverse grooves in the exposed surface of green concrete which ultimately defines a roadway including a supporting frame having spaced supporting wheels formed and adapted to straddle a road defining slab of green concrete, said frame including a first scoring element support extending transversely of the longitudinal axis of the frame, a plurality of scoring elements carried by said support and formed and adapted to impress grooves extending generally longitudinally of said frame and slab when said frame is moved longitudinally of said slab, a second scoring element support extending generally parallel to the longitudinal axis of said frame, said second support including a plurality of scoring elements, means for moving said second support generally transversely of the longitudinal axis of said slab to impress transverse grooves in said slab, means for moving said frame in said longitudinal direction, said scoring elements on said first and second supports being defined by spaced wire-like loops, and means for intermittently moving said second support transversely of said longitudinal axis. 1

7. A scoring machine for selectively impressing grooves in the exposed surface of a roadway formed from a cementitious material, including a frame having front and rear supporting wheels arranged so as to straddle said roadway, said frame including scoring elements for selectively impressing grooves in the surface of said material, each wheel including an arm carried thereby and extending inwardly of the machine, each arm being movable with pivotal steering movement of the wheel, each arm having sensing elements carried thereon and formed and adapted to sense the position of its associated wheel relative to the adjacent edge of said material, and means operated by said sensing means for turning its associated wheel away from said material whenever that wheel is more closely to said material than a predetermined spatial relation, said sensing elements comprising a first light projecting beam element carried by said arm and a light sensitive element carried by said arm in spaced relation to said light projecting element, said elements being carried by said arm at positions forwardly of each wheel.

8. A machine for selectively impressing longitudinal and transverse grooves in the exposed surface of a cementitious road material including a supporting frame having front and rear suppbrting wheels, said frame including a central portion and arms adapted to extend generally longitudinally of said machine, said supporting wheels being carried by said arms, each arm being pivotally mounted on said central portion for folding movement between positions extended generally longitudinally of said central portions and a position extending generally alongside said central portion, means for holding said arms in said longitudinally extended position, one of said forward wheels including a crank arm connected to a support thereof, a hydraulic cylinder connected between the supporting arm for said one wheel and said rank arm to cause turning movement of said one wheel upon extension and retraction of said hydraulic cylinder, and linkage means between said crank arm and a crank arm carried with a support for the other front wheel to cause a corresponding movement of said other front wheel in response to turning movement of said first named front wheel.

9. A machine for selectively impressing longitudinal and transverse grooves in the exposed surface of a cementitious road material including a supporting frame having from and rear supporting wheels, said frame including a central portion and arms adapted to extend generally longitudinally of said machine, said supporting wheels being carried by said arms, each arm being pivotally mounted on said central portion on pivots having axes positioned inwardly of the front and rear margins of said central portion and beneath said central portion for folding movement between positions extending generally longitudinally of said central portions and a position extending beneath said central portion, and means for holding said arms in said longitudinally extended position.

10. A machine for selectively impressing longitudinal and transverse grooves in the exposed surface of a cementitious road material including a supporting frame having front and rear supporting wheels, said frame including a central portion and arms adapted to extend generally longitudinally of said machine, said supporting wheels being carried by said arms, each arm being pivotally mounted on said central portion for folding movement between positionsextended generally longitudinally of said central portions and a position extending generally alongside said central portion, means for holding said arms in said longitudinally extended position, hydraulic cylinder means interconnected with one of said front wheels for causing a turning movement thereof and hydraulic cylinder means connected to one of said rear wheels to cause a selective turning movement thereof, linkage means between one front wheel and the other front wheel to produce simultaneous turning movement of said front wheels together, linkage means between said one rear wheel and the other rear wheel to cause simultaneous turning movement of said rear wheels together, and power means for operating the hydraulic cylinder means for said front wheel and separate power means for, operating the hydraulic cylinder means for said rear wheels, said power means for said front and rear wheel being operable independently of one another.

11. The structure of claim 10 wherein each linkage means includes adjustable connecting links to enable usage of each said linkage means at variant lateral spacings of said arm structures relative to one another.

12. A machine for selectively impressing grooves in the exposed surface of green concrete which ultimately defines a roadway including a supporting frame having spaced supporting wheels formed and adapted to straddle a road defining slab of green concrete, a subframe extending transversely of said supporting frame and beneath said supporting frame, extensible means for raising and lowering said subframe with respect to said supporting frame, said subframe having track means extending transversely of said supporting frame, a carriage supported in said track means for movement transversely of said supporting frame, and scoring elements carried by said carriage in depending relation thereto, said subframe being pivotally mounted on said extensible means for rocking movement about an axis extending transversely of said supporting frame, and means for holding said subframe and carriage at a selected angular position relative to said extensible means.

13. The structure of claim 12 characterized by and including cable means for limiting the downward movement of said subframe and carriage with respect to said supporting frame.

14. The structure of claim 12 wherein said subframe is defined by a plurality of pivotally connected sections positioned end-to-end and extending transversely of the machine, and means are included for holding said sections at selected angular dispositions relative to one another.

15. The structure of claim 12 wherein said track means are defined by guide tracks removably clamped on said subframe.

16. The structure of claim 12 characterized by and including spring means connected between said extensible means and forward and rear portions of said subframe to thereby bias said subframe toward a planar disposition at right angles to said extensible means.

17. The structure of claim 12 characterized by and including extensible power means between said subframe and said extensible means for adjusting the planar disposition of said subframe relative to said extensible means. 

1. A scoring element assembly for use in forming grooves of small width and relatively shallow depth in green concrete including an elongated supporting frame and resilient, looped wire-like elements carried at generally equally spaced intervals along said frame, said elements being sufficiently resilient and having a shape such that when said frame and loops have their weight essentially supported by a bed of green concrete or the equivalent and are moved transversely to the length of said frame along said concrete, said loops will impress grooves generally parallel to the direction of movement without substantial displacement of said concrete other than in directions generally downward from the general plane of the surface of the concrete.
 2. The structure of claim 1 wherein said loops are generally elliptical in form with the major axis thereof generally parallel to the direction of movement.
 3. The structure of claim 1 wherein said frame has a supporting strap carried thereby and extending generally parallel to said direction of movement, said strap having forward and rear portions with guiding apertures with said elements extended therethrough.
 4. The structure of claim 1 wherein said frame includes support tube associated with each element and with opposite ends of each element secured within said tube.
 5. A machine for selectively impressing longitudinal and transverse grooves in the exposed surface of green concrete which ultimately defines a roadway including a supporting frame having spaced supporting wheels formed and adapted to straddle a road defining slab of green concrete, said frame including a first scoring element support extending transversely of the longitudinal axis of the frame, a plurality of scoring elements carried by said support and formed and adapted to impress grooves extending generally longitudinally of said frame and slab when said frame is moved longitudinally of said slab, a second scoring element support extending generally parallel to the longitudinal axis of said frame, said second support including a plurality of scoring elements defined by a plurality of spaced wire-like loops, means for moving said second support generally transversely of the longitudinal axis of said slab to impress transverse grooves in said slab, means for moving said frame in said longitudinal direction, and means for intermittently moving said second support transversely of said longitudinal axis.
 6. A machine for selectively impressing longitudinal and transverse grooves in the exposed surface of green concrete which ultimately defines a roadway including a supporting frame having spaced supporting wheels formed and adapted to straddle a road defining slab of grEen concrete, said frame including a first scoring element support extending transversely of the longitudinal axis of the frame, a plurality of scoring elements carried by said support and formed and adapted to impress grooves extending generally longitudinally of said frame and slab when said frame is moved longitudinally of said slab, a second scoring element support extending generally parallel to the longitudinal axis of said frame, said second support including a plurality of scoring elements, means for moving said second support generally transversely of the longitudinal axis of said slab to impress transverse grooves in said slab, means for moving said frame in said longitudinal direction, said scoring elements on said first and second supports being defined by spaced wire-like loops, and means for intermittently moving said second support transversely of said longitudinal axis.
 7. A scoring machine for selectively impressing grooves in the exposed surface of a roadway formed from a cementitious material, including a frame having front and rear supporting wheels arranged so as to straddle said roadway, said frame including scoring elements for selectively impressing grooves in the surface of said material, each wheel including an arm carried thereby and extending inwardly of the machine, each arm being movable with pivotal steering movement of the wheel, each arm having sensing elements carried thereon and formed and adapted to sense the position of its associated wheel relative to the adjacent edge of said material, and means operated by said sensing means for turning its associated wheel away from said material whenever that wheel is more closely to said material than a predetermined spatial relation, said sensing elements comprising a first light projecting beam element carried by said arm and a light sensitive element carried by said arm in spaced relation to said light projecting element, said elements being carried by said arm at positions forwardly of each wheel.
 8. A machine for selectively impressing longitudinal and transverse grooves in the exposed surface of a cementitious road material including a supporting frame having front and rear supporting wheels, said frame including a central portion and arms adapted to extend generally longitudinally of said machine, said supporting wheels being carried by said arms, each arm being pivotally mounted on said central portion for folding movement between positions extended generally longitudinally of said central portions and a position extending generally alongside said central portion, means for holding said arms in said longitudinally extended position, one of said forward wheels including a crank arm connected to a support thereof, a hydraulic cylinder connected between the supporting arm for said one wheel and said rank arm to cause turning movement of said one wheel upon extension and retraction of said hydraulic cylinder, and linkage means between said crank arm and a crank arm carried with a support for the other front wheel to cause a corresponding movement of said other front wheel in response to turning movement of said first named front wheel.
 9. A machine for selectively impressing longitudinal and transverse grooves in the exposed surface of a cementitious road material including a supporting frame having front and rear supporting wheels, said frame including a central portion and arms adapted to extend generally longitudinally of said machine, said supporting wheels being carried by said arms, each arm being pivotally mounted on said central portion on pivots having axes positioned inwardly of the front and rear margins of said central portion and beneath said central portion for folding movement between positions extending generally longitudinally of said central portions and a position extending beneath said central portion, and means for holding said arms in said longitudinally extended position.
 10. A machine for selectively impressing longitudinal and transverse grooves in the exposeD surface of a cementitious road material including a supporting frame having front and rear supporting wheels, said frame including a central portion and arms adapted to extend generally longitudinally of said machine, said supporting wheels being carried by said arms, each arm being pivotally mounted on said central portion for folding movement between positions extended generally longitudinally of said central portions and a position extending generally alongside said central portion, means for holding said arms in said longitudinally extended position, hydraulic cylinder means interconnected with one of said front wheels for causing a turning movement thereof and hydraulic cylinder means connected to one of said rear wheels to cause a selective turning movement thereof, linkage means between one front wheel and the other front wheel to produce simultaneous turning movement of said front wheels together, linkage means between said one rear wheel and the other rear wheel to cause simultaneous turning movement of said rear wheels together, and power means for operating the hydraulic cylinder means for said front wheel and separate power means for operating the hydraulic cylinder means for said rear wheels, said power means for said front and rear wheel being operable independently of one another.
 11. The structure of claim 10 wherein each linkage means includes adjustable connecting links to enable usage of each said linkage means at variant lateral spacings of said arm structures relative to one another.
 12. A machine for selectively impressing grooves in the exposed surface of green concrete which ultimately defines a roadway including a supporting frame having spaced supporting wheels formed and adapted to straddle a road defining slab of green concrete, a subframe extending transversely of said supporting frame and beneath said supporting frame, extensible means for raising and lowering said subframe with respect to said supporting frame, said subframe having track means extending transversely of said supporting frame, a carriage supported in said track means for movement transversely of said supporting frame, and scoring elements carried by said carriage in depending relation thereto, said subframe being pivotally mounted on said extensible means for rocking movement about an axis extending transversely of said supporting frame, and means for holding said subframe and carriage at a selected angular position relative to said extensible means.
 13. The structure of claim 12 characterized by and including cable means for limiting the downward movement of said subframe and carriage with respect to said supporting frame.
 14. The structure of claim 12 wherein said subframe is defined by a plurality of pivotally connected sections positioned end-to-end and extending transversely of the machine, and means are included for holding said sections at selected angular dispositions relative to one another.
 15. The structure of claim 12 wherein said track means are defined by guide tracks removably clamped on said subframe.
 16. The structure of claim 12 characterized by and including spring means connected between said extensible means and forward and rear portions of said subframe to thereby bias said subframe toward a planar disposition at right angles to said extensible means.
 17. The structure of claim 12 characterized by and including extensible power means between said subframe and said extensible means for adjusting the planar disposition of said subframe relative to said extensible means. 